Checking fuel flow

[ringer]

Am having problems again with starting, though this time I suspect I have a blocked fuel pipe.
Cannot remember which way to position the manual tap for reserve, and which for normal. Bike starts and runs ok when the lever on this tap is vertical (pointing down), so I'm guessing this is the reserve position. Can someone please confirm this. And yes, I do have plenty of fuel in the tank.
My fuel pipes are black plastic so very difficult to tell if fuel is flowing unless I pull a pipe off. Not very easy at the side of the road. Can you get/use clear fuel pipes, and if so is it possible to see the fuel flowing in them? Is there such a thing as a clear fuel pipe with a paddle in so you can see the flow? Not even sure exactly how much flow there is in the pipes when the bike is running.

[kangurada]

Manual taps are generally ON after the first quarter turn and RESERVE is beyond that after the next quarter turn. Makes ergonomic sense that way, and so it is on the manual taps on my Kanguro. Can be tested by tilting tank (or even bike!) with the pipe off ....